Why does Windows 10 need Message Queuing service and why the service is installed by default?

I've upgraded two systems from Windows 7 to 10 and both have the MSMQ service installed after upgrade. None of those systems had it installed before.

The presence of the service is not a problem in itself, but it or a dependency service is listening on TCP port 80 via Microsoft HTTP API (System process PID 4) and I can't start Apache because of that.

So far my searches for answers have been fruitless, because most results I find are dealing with setup and configuration of MSMQ but not it's purpose on a freshly installed Win10 system.

I have two questions:

1. What is the purpose of MSMQ service in Windows 10 systems?


2. Can the service(s) be disabled (or set to manual start) without any ill side effects?

Answer

What is MSMQ?

From Microsoft:

Microsoft Message Queuing (MSMQ) technology enables applications
running at different times to communicate across heterogeneous
networks and systems that may be temporarily offline. MSMQ provides
guaranteed message delivery, efficient routing, security, and
priority-based messaging. It can be used to implement solutions for
both asynchronous and synchronous messaging scenarios.

From a user on Stack Overflow:

It's just a queue manager.

You can Send objects (serialized) to the queue where they will stay
until you Receive them. It's normally used to send messages or objects
between applications in a decoupled way.

It has nothing to do with webservices, they are two different things

Can you disable it? What happens?

When the MSMQ service is uninstalled the following actions are also
carried out:

1. All existing queues and queue configuration information is deleted


2. All messages contained in those queue and the system dead letter queue
   (DLQ) is deleted

(Source)

In a nutshell

The service started coming installed on Windows 8 and up systems (to my knowledge), which may be why you didn't see it on 7. Removing it only affects itself, and if you aren't using it then nothing should be affected.

Disabling the service you know how to do, but you can also remove it using Add & Remove Features